The glass ceiling preventing talented black and minority ethnic managers from stepping up into top executive jobs is still rigidly in place despite a range of high-profile government diversity initiatives over the last few years, according to research.

Boardrooms across the public and private sectors remain stubbornly white, says a report, Race to the Top, by the charity Business in the Community (BITC). It analysed data between 2000 and 2007, and concludes that management prospects are disproportionately bleak for people from a black or minority ethnic (BME) background - and likely to worsen over the next decade unless action is taken.

Sandra Kerr, national director for the BITC's Race for Opportunity campaign, called the findings "devastating".

Action was needed right away to "shatter the last glass ceiling", and the government needed to lead by example. "There is definitely a need to put this at the heart of the agenda for government and business," she said.

The report suggests that since 2000 a number of government-led legal measures and race equality initiatives designed to increase top-level opportunities for BME managers have had minimal impact.

These include the strengthening of the 1976 Race Relations Act, the creation of an ethnic minority and employment taskforce, the race equality and diversity action plan, and specialist employment advisers.

Kerr said it was time for a "rethink" in the government and in boardrooms. The report was intended "not merely to flag up how terrible the situation is, but to start a process for improving things. Chief executives need to walk into their boardroom, take a look around, and ask themselves: 'Does this represent in any way, shape or form what I see around me when I walk around streets every day?' Then they need to do something about it."

Wilfred Emmanuel-Jones, a businessman, farmer and Conservative prospective parliamentary candidate for Chippenham at the next general election, said: "Equality is very low down on the list of priorities in most organisations.

"To become a member of this elite club of senior managers and directors, it isn't simply a question of whether you are able to do the job - other things come into play: social background, how you spend your leisure time, whether other members of that club would like to spend social time with you. All too often, people of colour fail these tests."

The report suggests that a handful of high-profile, top black and ethnic minority executives, such as Suma Chakrabarti, permanent secretary at the Ministry of Justice, Victor Adebowale, chief executive of the social care business Turning Point, and the private equity boss Damon Buffini are prominent exceptions.

The gap between ethnic minority representation in senior management and numbers in the wider population is particularly worrying, the report concludes.

"Taking trend rates of the last seven years and projecting them forward shows that, if anything, the gap will widen," the report says. "The depressing implication is that there may still be a colour bar to management jobs 33 years after the passing of the Race Relations Act."